Abstract: An ultrasonic device includes an ultrasonic sensor, a wiring member, and a housing, in which the wiring member has a covered wire that covers a signal line coupled to the ultrasonic sensor via an insulating layer, and a conductive member that is electrically coupled with the covered wire, the housing has a plurality of housing components having conductivity, and covers the ultrasonic sensor with the plurality of housing components, and the conductive member is electrically coupled to and held by the plurality of housing components.

Abstract: A method for manufacturing a plurality of mechanical resonators (100) in a manufacturing wafer (10), the resonators being intended to be fitted to an adjusting member of a timepiece, the method comprising the following steps: (a) manufacturing a plurality of resonators in at least one reference wafer according to reference specifications, such manufacture comprising at least one lithography step to form patterns of the resonators on or above the reference wafer and a step of machining in the reference plate using the patterns; (b) for the at least one reference plate, establishing a map indicative of the dispersion of stiffnesses of the resonators relative to an average stiffness value; (c) dividing the map into fields and determining a correction to be made to the dimensions of the resonators for at least one of the fields in order to reduce the dispersion; (d) modifying the reference specifications for the lithography step so as to make the corrections to the dimensions for the at least one field in the lit

Abstract: An acoustic wave device includes: a piezoelectric substrate bonded on a support substrate, a surface including protruding portions and/or recessed portions being interposed between the piezoelectric substrate and the support substrate; a first acoustic wave resonator that includes first electrode fingers with a first average pitch and is disposed on the piezoelectric substrate in a first region where an average interval between the protruding portions and/or the recessed portions in a direction in which the first electrode fingers are arranged is a first interval; and a second acoustic wave resonator that includes second electrode fingers with a second average pitch different from the first average pitch, and is disposed on the piezoelectric substrate in a second region where an average interval between the protruding portions and/or the recessed portions in a direction in which the second electrode fingers are arranged is a second interval different from the first interval.

Abstract: An acoustic wave device includes a material layer which has Euler angles and an elastic constant at the Euler angles, a piezoelectric body which includes first and second principal surfaces opposing each other, is laminated directly or indirectly on the material layer so that the second principal surface is on the material layer side and has Euler angles, and whose elastic constant at the Euler angles, and an IDT electrode which is disposed on at least one of the first principal surface and the second principal surface of the piezoelectric body. At least one elastic constant among elastic constants C11 to C66 of the material layer not equal to 0 and at least one elastic constant among elastic constants C11 to C66 of the piezoelectric body not equal to 0 have opposite signs to each other.

Abstract: An ultrasonic sensing device includes a housing, a piezoelectric assembly, a board and a plurality of fixing members. The housing includes a connecting board being a metal board and a supporting shell being a plastic member. The supporting shell includes a bottom wall opposite to a disposing opening of the connecting board and a surrounding side wall integrally surrounding and connecting to the bottom wall. The surrounding side wall encloses a portion of the connecting board. The piezoelectric assembly includes an encapsulating body and a piezoelectric sheet enclosed by the encapsulating body. The encapsulating body is disposed on the bottom wall and surrounded by the surrounding side wall. The piezoelectric sheet has a sensing surface exposed to the encapsulating body and facing the bottom wall. The fixing members fix the board on the connecting board, thereby pressing the sensing surface of the piezoelectric sheet to the bottom wall.

Abstract: An elastic wave device includes a supporting substrate including an upper surface including a recessed portion, a piezoelectric thin film on the supporting substrate to cover the recessed portion of the supporting substrate, an IDT electrode on a main surface of the piezoelectric thin film, the main surface being adjacent to the supporting substrate, and an intermediate layer on a main surface of the piezoelectric thin film, the main surface being remote from the supporting substrate. A space is defined by the supporting substrate and the piezoelectric thin film. The IDT electrode faces the space. Through holes are provided in the piezoelectric thin film and the intermediate layer to extend from a main surface of the intermediate layer to the space, the main surface being remote from the piezoelectric thin film. The elastic wave device further includes a cover member on the intermediate layer and covering opening ends of the through holes.

Abstract: An ultrasound probe including a probe body having a mounting area and a flexible lip around said mounting area for sealing a space between the mounting area and a subject contacted by the ultrasound probe; and a number of ultrasound transducer elements mounted in the mounting area. The probe body further includes an inlet to said space and an outlet from said space for facilitating a fluid flow through said space when sealed. Also included are an ultrasound system including such an ultrasound probe and a method of subjecting a subject to ultrasound waves generated with such an ultrasound probe.

Abstract: In an elastic wave device, an IDT electrode is provided on a piezoelectric substrate and a first silicon oxide film covers the IDT electrode. A high-acoustic-velocity dielectric film covers the first silicon oxide film. A second silicon oxide film is provided on the high-acoustic-velocity dielectric film. The piezoelectric substrate is made of lithium niobate. The high-acoustic-velocity dielectric film propagates longitudinal waves at an acoustic velocity higher than an acoustic velocity of longitudinal waves propagating through the first silicon oxide film. The high-acoustic-velocity dielectric film is provided at a distance of about (t1+t2)×0.42 or less from a first main surface of the piezoelectric substrate in a thickness direction of the piezoelectric substrate.

Abstract: An acoustic wave device includes a high-acoustic-velocity film, a low-acoustic-velocity film provided on the high-acoustic-velocity film, a piezoelectric layer provided on the low-acoustic-velocity film, and an IDT electrode provided on the piezoelectric layer. An acoustic velocity of bulk waves propagating through the high-acoustic-velocity film is higher than an acoustic velocity of acoustic waves propagating through the piezoelectric layer. An acoustic velocity of bulk waves propagating through the low-acoustic-velocity film is lower than an acoustic velocity of bulk waves propagating through the piezoelectric layer. The low-acoustic-velocity film includes a material including hydrogen atoms.

Abstract: An acoustic resonator includes a membrane layer disposed on an insulating layer; a cavity formed by the insulating layer and the membrane layer and having a hydrophobic layer disposed on at least one of a portion of an upper surface of the cavity and a portion of a lower surface of the cavity; and a resonating portion disposed on the cavity and having a second electrode on a piezoelectric layer on a first electrode.

Abstract: A fuel cell may include a cell stack including a plurality of unit cells stacked in a first direction, first and second end plates disposed at corresponding first and second end portions of the cell stack, at least one clamping member coupled to the first and second end plates to clamp the plurality of unit cells in the first direction and configured to generate heat in a response to a control signal, and a controller configured to generate the control signal based on the temperature of the cell stack.

Abstract: A moveable micromachined member of a microelectromechanical system (MEMS) device includes an insulating layer disposed between first and second electrically conductive layers. First and second mechanical structures secure the moveable micromachined member to a substrate of the MEMS device and include respective first and second electrical interconnect layers coupled in series, with the first electrically conductive layer of the moveable micromachined member and each other, between first and second electrical terminals to enable conduction of a first joule-heating current from the first electrical terminal to the second electrical terminal through the first electrically conductive layer of the moveable micromachined member.

Abstract: An acoustic wave device includes a high-acoustic-velocity film, a piezoelectric layer provided directly or indirectly on the high-acoustic-velocity film, an IDT electrode provided on the piezoelectric layer, and a dielectric film provided on the piezoelectric layer to cover the IDT electrode. An acoustic velocity of bulk waves propagating through the high-acoustic-velocity film is higher than an acoustic velocity of acoustic waves propagating through the piezoelectric layer. The dielectric film includes a material including hydrogen atoms.

Abstract: An acoustic resonator includes a membrane layer disposed on an insulating layer; a cavity formed by the insulating layer and the membrane layer; a resonating portion disposed on the cavity and having a first electrode, a piezoelectric layer, and a second electrode stacked thereon; a protective layer disposed on the resonating portion; and a hydrophobic layer formed on the protective layer.

Abstract: An elastic wave device includes an interdigital transducer electrode including electrode fingers provided on a first principal surface of a piezoelectric thin film. A conductive layer is provided on a second principal surface of the piezoelectric thin film. An elastic wave propagates in the piezoelectric thin film in an S0 mode of a plate wave, and a piezoelectric thin film portion in a region below spaces between the electrode fingers of the interdigital transducer electrode is displaced by a greater amount than each electrode finger and a piezoelectric thin film portion in a region below each electrode finger.

Abstract: Acoustic filtering circuitry includes an input node, an output node, a signal transmission path, a series acoustic resonator, and a shunt acoustic resonator. The signal transmission path is between the input node and the output node. The series acoustic resonator is coupled between the input node and the output node in the signal transmission path. Further, a temperature coefficient of frequency (TCF) of a parallel resonance frequency of the series acoustic resonator is positive. The shunt acoustic resonator is coupled between the signal transmission path and ground. Further, a TCF of a series resonance frequency of the shunt acoustic resonator is negative. By providing the TCF of the series acoustic resonator and the shunt acoustic resonator in this manner, self-heating of the acoustic filtering circuitry may be significantly reduced, thereby improving the performance of the acoustic filtering circuitry.

Abstract: A method of manufacturing a bulk acoustic wave resonator includes: forming a sacrificial layer on a substrate protection layer; forming a membrane layer on the substrate protection layer to cover the sacrificial layer; and forming a cavity by removing the sacrificial layer using a gas mixture comprising a halide-based gas and an oxygen-containing gas, wherein a mixture ratio of the halide-based gas to the oxygen-containing gas in the gas mixture is in a range from 1.5 to 2.4.

Abstract: A MEMS piezoelectric device includes a monolithic semiconductor body having first and second main surfaces extending parallel to a horizontal plane formed by first and second horizontal axes. A housing cavity is arranged within the monolithic semiconductor body. A membrane is suspended above the housing cavity at the first main surface. A piezoelectric material layer is arranged above a first surface of the membrane with a proof mass coupled to a second surface, opposite to the first surface, along the vertical axis. An electrode arrangement is provided in contact with the piezoelectric material layer. The proof mass causes deformation of the piezoelectric material layer in response to environmental mechanical vibrations. The proof mass is coupled to the membrane by a connection element arranged, in a central position, between the membrane and the proof mass in the direction of the vertical axis.

Abstract: An oven controlled MEMS timing device that includes a very small oscillator that can be heated very rapidly with very low power. The MEMS device includes a rectangular frame, a heated platform positing in the frame, and a pair of support beams that extend from the rectangular frame and hold the platform within a cavity of the frame to thermally isolate the platform. Moreover, the device includes a resonator attached to the platform by a pair of anchor beams, a heater that heats the platform to maintain a target temperature for the resonator and a thermistor that measures a temperature of the platform to provide a control loop for the heater.

Abstract: An active type temperature compensation resonator structure is provided, including a resonant body and a temperature compensation element embedded in the resonant body for a compensation current to pass therethrough. The temperature compensation element has a specified temperature coefficient of resistance that reflects the temperature of the resonant body. The magnitude of the compensated current corresponds to the reflected temperature of the resonant body. With the active type temperature compensation resonator structure, the temperature of the resonant body can be accurately reacted by the specified temperature coefficient of resistance, such that the temperature compensation element, through which the compensated current passes, can dynamically correspond to the temperature of the resonant body and accurately provide the resonant body with temperature compensation.

Abstract: A method of manufacturing resonation device (a quartz crystal oscillator) includes the steps of applying a thermosetting thermal insulating connection material and an electrically-conductive connection material, which is higher in curing temperature than the thermosetting thermal insulating connection material, on a principal surface of a substrate, mounting fixation terminals of a resonator (a quartz crystal resonator), which has a heating element, and to which the fixation terminals and connection terminals are connected, in application positions of the insulating connection material on the substrate, and connection terminals in application positions of the electrically-conductive connection material, and heating the insulating connection material and the electrically-conductive connection material based on a reflow profile to make the insulating connection material and the electrically-conductive connection material cure in this order.

Abstract: A method of manufacturing resonation device (a quartz crystal oscillator) includes the steps of applying a thermosetting thermal insulating connection material and an electrically-conductive connection material, which is higher in curing temperature than the thermosetting thermal insulating connection material, on a principal surface of a substrate, mounting fixation terminals of a resonator (a quartz crystal resonator), which has a heating element, and to which the fixation terminals and connection terminals are connected, in application positions of the insulating connection material on the substrate, and connection terminals in application positions of the electrically-conductive connection material, and heating the insulating connection material and the electrically-conductive connection material based on a reflow profile to make the insulating connection material and the electrically-conductive connection material cure in this order.

Abstract: An acoustic resonator device comprises: a substrate comprising a cavity or an acoustic mirror; a first electrode disposed over the substrate; a piezoelectric layer disposed over the first electrode; and a second electrode disposed over the piezoelectric layer. The first electrode or the second electrode, or both, are made of an electrically conductive material having a positive temperature coefficient.

Abstract: This disclosure provides systems, methods and apparatus related to acoustic resonators that include composite transduction layers for enabling selective tuning of one or more acoustic or electromechanical properties. In one aspect, a resonator structure includes one or more first electrodes, one or more second electrodes, and a transduction layer arranged between the first and second electrodes. The transduction layer includes a plurality of constituent layers. In some implementations, the constituent layers include one or more first piezoelectric layers and one or more second piezoelectric layers. The transduction layer is configured to, responsive to signals provided to the first and second electrodes, provide at least a first mode of vibration of the transduction layer with a displacement component along the z axis and at least a second mode of vibration of the transduction layer with a displacement component along the plane of the x axis and they axis.

Abstract: There are provided a multi-layer piezoelectric element which is capable of suppression of occurrence of an imperfect area, suffers from no development of leakage current even with moisture intrusion, has long-term freedom from variations in displacement and can achieve stable driving, as well as to provide a piezoelectric actuator, an injection device, and a fuel injection system provided with the multi-layer piezoelectric element. A multi-layer piezoelectric element includes a stacked body in which piezoelectric layers and internal electrodes acting as positive and negative internal electrodes are laminated; an inorganic coating attached to a side surface of the stacked body where ends of both the positive internal electrodes and the negative internal electrodes are exposed; and metal particles composed predominantly of a metal element contained in the internal electrodes, the metal particles dispersed in the inorganic coating.

Abstract: An acoustic wave device includes: a substrate; a lower electrode that is located on the substrate; a piezoelectric film that is located on the lower electrode and made of aluminum nitride of which a ratio of a lattice constant in a c-axis direction to a lattice constant in an a-axis direction is smaller than 1.6; and an upper electrode that is located on the piezoelectric film and faces the lower electrode across the piezoelectric film.

Abstract: A crystal device is provided, in which a peeling of a bonding material is prevented by using the bonding material having a thermal expansion coefficient which is between the coefficients in a first direction and a second direction of a bonding surface of a crystal element. A crystal device includes a rectangular crystal element formed with a crystal material that includes an excitation part and a frame surrounding the excitation part. The device further includes a rectangular base bonded to a principal surface of the frame, and a lid bonded to another principal surface of the frame; and the frame, the base and the lid have edges respectively along a first direction and a second direction intersecting with the first direction. The bonding material is applied having a thermal expansion coefficient that is between the coefficients in the first direction and second direction of the crystal element.

Abstract: An acoustic wave filter includes series resonators and parallel resonators that have a piezoelectric film on an identical substrate and have a lower electrode and an upper electrode, wherein: one of the series resonators and the parallel resonators have a temperature compensation film on a face of the lower electrode or the upper electrode that is opposite to the piezoelectric film in a resonance region, the compensation film having an elastic constant of a temperature coefficient of which sign is opposite to a sign of a temperature coefficient of an elastic constant of the piezoelectric film; and the other have an added film on the same side as the temperature compensation film on the lower electrode side or the upper electrode side compared to the piezoelectric film in the resonance region in the one of the series resonators and the parallel resonators.

Abstract: Devices having piezoelectric material structures integrated with substrates are described. Fabrication techniques for forming such devices are also described. The fabrication may include bonding a piezoelectric material wafer to a substrate of a differing material. A structure, such as a resonator, may then be formed from the piezoelectric material wafer.

Abstract: A resonant transducer comprising: a vibration plate; and a piezoelectric element including a piezoelectric film and an upper electrode that are laminated on the vibration plate, wherein a compressive stress is applied to the piezoelectric film.

Abstract: A piezoelectric element used between a lowest use temperature T1 and a highest use temperature T2, includes a first electrode, a piezoelectric layer provided on the first electrode and made of a piezoelectric material including a composite oxide having a perovskite structure, the piezoelectric material having a morphotropic phase boundary which is inclined with respect to a temperature axis, and the piezoelectric material satisfying at least one of formulas T3?T1?T4 and T3?T2?T4, where T3 is a temperature corresponding to the morphotropic phase boundary at a lowest point and T4 is a temperature corresponding to the morphotropic phase boundary at a highest point and a second electrode provided on the piezoelectric layer.

Abstract: A vibrating element has a drive mode, and first and second detection modes in which the vibrating element vibrates in a direction orthogonal to a vibration direction in the drive mode. In frequency-temperature characteristic curves representing a change in frequency due to a change in temperature in the respective modes with a horizontal axis representing an ambient temperature and a vertical axis representing a change in frequency, when a turnover temperature of the frequency-temperature characteristic curve in the drive mode is Ta [° C.], a turnover temperature of the frequency-temperature characteristic curve in the first detection mode is Tb [° C.], and a turnover temperature of the frequency-temperature characteristic curve in the second detection mode is Tc [° C.], Ta is lower than Tb and Tc, or Ta is higher than Tb and Tc.

Abstract: Apparatus and methods for control of charge in a semiconductor material of a mechanical resonating structure are described. Controlling the charge of the material may control the material properties of the semiconductor, such as the stiffness. Such control may result in changes in the behavior of the mechanical resonating structure, allowing for control and tuning of the behavior of the mechanical resonating structure.

Abstract: Methods, systems, and devices for providing cooling for a mobile device using piezoelectric active cooling devices. Some embodiments utilize piezoelectric actuators that oscillate a planar element within an air channel to fan air within or at an outlet of the air channel. The air channel may be defined by at least one heat dissipation surface in thermal contact with components of the mobile device that generate excess waste heat. For example, the air channel may include a surface that is in thermal contact with a processor of the mobile computing device. In embodiments, the piezoelectric active cooling device may be used in an air gap between stacked packages in a package on package (PoP) processor package. The described embodiments provide active cooling using low power, can be controlled to provide variable cooling, use highly reliable elements, and can be implemented at low cost.

Abstract: A micromachined structure, comprises a substrate and a cavity in the substrate. The micromachined structure comprises a membrane layer disposed over the substrate and spanning the cavity.

Abstract: A head has a base and a piezoelectric element which is superimposed on and fastened to the base in a thickness direction. The piezoelectric element has a plate-shaped piezoelectric body, and a common electrode and a individual electrode arranged so as to sandwich the piezoelectric body in the thickness direction. The base has a higher thermal expansion coefficient than the piezoelectric body (the piezoelectric element 23). The piezoelectric body has a tetragonal principal crystal phase, in which the degree of orientation of the c-axis toward one side in the thickness direction (positive side in z direction) in the region sandwiched by the common electrode and the individual electrode is 44% or more and 56% or less in terms of the Lotgering factor and in which the residual stress in the surface direction is 0 MPa or more and 35 MPa or less in the direction of compression.

Abstract: An acoustic wave device includes: a comb-like electrode provided on a piezoelectric substrate; and a first medium that covers the comb-like electrode and has at least a silicon oxide film in which an element is doped, wherein sonic speed in the silicon oxide film in which the element is doped is lower than sonic speed in an undoped silicon oxide film.

Abstract: An acoustic wave device includes: a piezoelectric thin film resonator including: a substrate; a lower electrode formed on the substrate; at least two piezoelectric films formed on the lower electrode; an insulating film sandwiched by the at least two piezoelectric films; and an upper electrode formed on the at least two piezoelectric films, wherein an area of the insulating film within a resonance region, in which the lower electrode and the upper electrode face each other across the at least two piezoelectric films, is different from an area of the resonance region.

Abstract: Mechanical resonating structures are described, as well as related devices and methods. The mechanical resonating structures may have a compensating structure for compensating temperature variations. The compensating structure may have multiple layers, one of which may have a stiffness that increases with increasing temperature and one of which may have a stiffness that decreases with increases in temperature.

Abstract: An acoustic wave device includes: a piezoelectric film located on a substrate; a lower electrode and an upper electrode facing each other across the piezoelectric film; a temperature compensation film located on a surface, which is opposite to the piezoelectric film, of at least one of the lower electrode and the upper electrode and having a temperature coefficient of elastic constant opposite in sign to a temperature coefficient of elastic constant of the piezoelectric film; and an additional film located on a surface of the temperature compensation film opposite to the piezoelectric film and having an acoustic impedance greater than an acoustic impedance of the temperature compensation film.

Abstract: A piezoelectric element includes a substrate, a lower electrode layer, a piezoelectric layer, and an upper electrode layer. The lower electrode layer is fixed to the substrate and the piezoelectric layer is formed on the lower electrode layer. The upper electrode layer is formed on piezoelectric layer. The lower electrode layer contains pores therein and has a larger thermal expansion coefficient than the piezoelectric layer.

Abstract: A polymer device includes: a pair of electrode layers; a polymer layer inserted between the pair of electrode layers; and an expansion-contraction suppression layer arranged between the pair of electrode layers, the expansion-contraction suppression layer being arranged away from the respective electrode layers, and the expansion-contraction suppression layer being configured to suppress expansion and contraction of the polymer layer.

Abstract: A temperature-compensated resonator including a body used in deformation, a core of the body being formed by ceramic. At least one part of the body includes a coating whose Young's modulus variation with temperature is of an opposite sign to that of the ceramic used for the core, so that at least the first order frequency variation with temperature of the resonator is substantially zero frequency.

Abstract: Aspects of the subject disclosure include, for example, constructing a mechanical resonating structure by applying an active layer on a surface of a compensating structure, wherein the compensating structure comprises one or more materials having an adaptive resistance to deform that reduces a variance in a resonating frequency of the mechanical resonating structure, wherein at least the active layer and the compensating structure form a mechanical resonating structure having a plurality of layers of materials, and wherein a thickness of each of the plurality of layers of materials results in a plurality of thickness ratios therebetween. Other embodiments are disclosed.

Abstract: An electromechanical transducer includes a first electromagnetic element and a second electromagnetic element, such as electrodes, disposed opposite to each other with a sealed cavity therebetween. The sealed cavity is formed by removing a sacrifice layer and then performing sealing. A sealing portion is formed by superposing a film of a hardened second sealing material that has fluidity at normal temperature on a film of a first sealing material that does not have fluidity at normal temperature.

Abstract: An acoustic resonator device comprises: a substrate comprising a cavity or an acoustic mirror; a first electrode disposed over the substrate; a piezoelectric layer disposed over the first electrode; and a second electrode disposed over the piezoelectric layer. The first electrode or the second electrode, or both, are made of an electrically conductive material having a positive temperature coefficient.

Abstract: A resonator device comprising a piezoelectric material and at least one electrode, the device also provided with a material with a positive coefficient of stiffness, wherein the material is disposed in the device as an electrode or as a separate layer adjacent the piezoelectric material formed as one or more layers in the device. The material that performs the temperature compensating function is selected from the group consisting of ferromagnetic metal alloys, shape-memory metal alloys, and polymers, wherein the selected material has a temperature coefficient that varies with the relative amounts of the individual constituents of the compositions and wherein the composition is selected to provide the material with the positive coefficient of stiffness.

Abstract: An acoustic resonator comprises: an acoustic resonator device comprises: a composite first electrode disposed over a substrate, the composite first electrode comprising: a first electrically conductive layer provided over the substrate; a first interlayer disposed on the first electrical conductive layer; a buried temperature compensation layer disposed over the first interlayer; a second interlayer disposed over the temperature compensation layer; a second electrically conductive layer disposed over the second interlayer, a piezoelectric layer disposed over the composite first electrode; and a second electrode disposed over the piezoelectric layer.

Abstract: A resonator device in which a piezoelectric material is disposed between two electrodes. At least one of the electrodes is formed of a nickel-titanium alloy having equal portions nickel and titanium.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, at least one interdigital transducer (IDT) electrode provided on the piezoelectric substrate, and an insulator layer to improve a temperature characteristic arranged so as to cover the IDT electrode. When a surface of the insulator layer is classified into a first surface region under which the IDT electrode is positioned and a second surface region under which no IDT electrode is positioned, the surface of the insulator layer in at least one portion of the second surface region is higher than the surface of the insulator layer from the piezoelectric substrate in at least one portion of the first surface region by at least about 0.001?, where the wavelength of an acoustic wave is ?.